1. Field of the Invention
The invention relates to a device for conveying fuel from a fuel tank to the internal combustion engine of a motor vehicle having a conveying unit communicating on the intake side with the fuel tank and on the pressurized side with the engine, and a return line which leads to a jet pump, located near a tank bottom, that pumps the excess fuel via a mixing region into a reserve pot, from which the conveying unit draws fuel.
2. Prior Art
In conveying devices in accordance with German Patent Disclosure DE 42 24 981 A1, with the aid of the jet pump an adequate filling of a reserve pot is to be assured, in which reserve pot the conveying unit is disposed and from which the fuel is fed to the engine. This is intended to assure a fuel reserve for the conveying unit even if the fuel tank is relatively empty, and this reserve assures that even relatively long hill uphill grades, for instance, can be overcome without problems. To fill the reserve pot, in the lower region near the tank bottom a mixing region is provided, by which both fresh fuel from the fuel tank and fuel returning from the engine are delivered to the reserve pot via an aspirating jet pump. In the mixing region near the jet pump, an opening is provided by way of which fresh fuel can enter the mixing region. To prevent the reserve pot from running empty once the engine and hence the conveying unit have been shutoff, this opening has a closing element in the form of a flap or valve plate, which opens whenever the engine is in operation and the jet pump is introducing returned fuel into the mixing region. However, this arrangement has the disadvantage of a complicated arrangement for closing the opening, which moreover requires a large amount of space. In addition, such closing elements, which are located at the inlet to the mixing region, cannot close the opening tightly, so that especially when the engine has been off for some time while the vehicle is parked on a slope, starting is impossible.